While PostgreSQL's adoption rate continues to accelerate, some folks wonder why that rate isn't even steeper given its impressive array of features. One can speculate that many of the reasons for not considering its adoption tend to be based on either outdated or misinformed sources.
In an effort to dispel some of the FUD (fear, uncertainty, and doubt) surrounding this impressive product, instead, I'll put forth several of the most commonplace reasons companies have for not investigating PostgreSQL further.
Personally, I'm, in my "environment" a PGSQL pioneer: when everyone use massivelly MySQL, I had searched a more powerfull and featured RDBMS... and I had selected PostgreSQL. 4 yeas ago. And It was the better thing that I did (in development, of course :D ).
Only MySQL seems to be "similar" to PG... but, IMHO, it still remain "poor".
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Source, Italia SW.